I am running what I believe to be the current version of restic (restic 0.15.2 compiled with go1.20.3 on linux/arm64) and after reading docs I was completely confused about “group-by” flag.
Reading the docs I assumed that I can use group-by option with backup command. Restic 0.15.2 documentation has a whole paragraph on using the group-by in the “Backing-up” section under “File change detection”:
“The previous backup snapshot, called “parent” snaphot in restic terminology, is determined as follows. By default restic groups snapshots by hostname and backup paths, and then selects the latest snapshot in the group that matches the current backup. You can change the selection criteria using the --group-by option, which defaults to host,paths. To select the latest snapshot with the same paths independent of the hostname, use paths. Or, to only consider the hostname and tags, use host,tags. Alternatively, it is possible to manually specify a specific parent snapshot using the --parent option. Finally, note that one would normally set the --group-by option for the forget command to the same value.”
Further in the manual “./restic backup --help” output is shown with group-by flag in the output.
However when I try to use group-by flag with backup command i get “unknown flag: --group-by”. It’s also not shown as a valid flag when I run “./restic backup --help”.
Thank you for your reply. I thought I was using docs for v0.15.2. I did use Google search but the window that I opened from search results says “Backing up - restic 0.15.2 documentation” and it does contain description of “group-by” flag, hence my confusion. See attached screenshot: